The present invention relates to an auger conveyor arrangement for a harvesting machine and particularly to one in which the conveyor auger is supported intermediately as well as adjacent its end. A particular application of the invention may be in a platform auger arrangement or cross auger of the header of a combine harvester.
As is well known, in combine headers the function of the cross conveyor is to receive crop material gathered from a field and converge it laterally for delivery to a feeder house, often situated at the center of the header, for transfer to a crop separating device in the main body of the combine. Pursuing the goals of increased harvesting efficiency and labor productivity, combines are built with ever bigger capacity separators, demanding a high crop material feed rate which is more easily satisfied by providing a wider header gatherer than by a higher combine forward speed. Combine header augers have generally been supported only at their opposite ends but in recent years, larger combines have been introduced with headers of such width that it becomes only marginally economic or practical to support a conveyor auger in this way. In the typical installation, the auger is most heavily loaded near its center where it delivers crop material to the feeder house and, if the auger itself is insufficiently stiff, deflection under load may result in contact between the auger and associated fixed conveying surfaces resulting in unacceptable wear and noise. A possible alternative, making an auger stiff enough by increasing its core tube diameter, may also be unacceptable because of the corresponding increase in flighting diameter required to maintain conveyor capacity and resulting increase in cost and weight.
It is already known to provide a central support in a combine harvester platform auger, see for example, U.S. Pat. No. 3,977,164, Ashton. However, the form of support disclosed by Ashton and that of intermediate supports for auger conveyors in general, tend to complicate assembly and disassembly of the individual auger sections. If adjacent auger portions are connected across the support, problems of alignment and the possibility of inducing undesirable stresses at the support area arise. Conventional intermediate support configurations often require the acceptance of an adverse effect on material handling adjacent the support because of the interruption in the conveying surfaces that they require.